A stagehands labor union plans to picket Michelle Obama’s book tour event in Tacoma on Sunday after claiming she won’t support the group in a labor dispute.

“I think the most important thing is for Michelle Obama to look backstage at the workers on her event and make sure that they’re also receiving healthcare,” said Bess Sullivan, vice president for IATSE #15, which represents Western Washington theatrical workers and technicians.

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IATSE #15 has been in ongoing negotiations with Rhino Staging Northwest, which was hired to staff Obama’s Tacoma event, over wages, health insurance, and safety concerns on the job. Rhino workers voted to unionize in 2015 but said they have been in contract negotiations since then.

The union sent Obama’s staff a letter in January asking her to sign a nation-wide agreement with IATSE to ensure workers at her events have pension contributions, health care, and property safety measures in place. However, the union says they have yet to hear a response.

“It’s incredibly frustrating, because we need the people who are leading us to walk the walk and not just serve lip service,” Sullivan said.

In Obama’s book Becoming, she describes growing up in a union household and fighting for healthcare. However, Sullivan said she would like to see Obama demonstrate those values.

“It’s appalling that when they do their own events that they’re not following what she’s talking about on stage,” Sullivan said.